1. Gravel A staple of both modernist landscapes and Provençal-style gardens, gravel is making a comeback. Choose crushed stone over pea gravel, which is a nonrenewable resource.

2. Pavers A local stone (bluestone in the Northeast, sandstone in the Southwest) will look more natural with your area's native plants and soil— and is better for the environment than stone imported from great distances.

3. Decomposed Granite This sandlike ground cover has an attractive pink tint and would work well in an outdoor dining area.

4. Lawn Big lawns are out; what's in, says Orr, are "lawns with a purpose." These smaller areas, framed by stone or gravel, act more like rugs than wall-to-wall carpeting. Don't rule out artificial turf: The new synthetic lawns are dead ringers for the real thing. Try easyturf.com or foreverlawn.com.